Cylinder questions

Reply Subscribe

Thread Tools

Search this Thread

Nov 22, 2012 | 09:20 AM

Jason6969

Thread Starter

Junior User

Joined: Jan 2007

Posts: 99

Likes: 0

From: Southern Md.

Cylinder questions

[/IMG]Anyone know what would cause this? 300 six 1989, 130,000 pulled apart for head gasket issues. no scratches felt when you run your fingernail across it. carbon? only visible in a couple cylinders this is the worst one.

Thanks,
Ross

Nov 22, 2012 | 09:41 AM

68cabby

Laughing Gas

Joined: Aug 2011

Posts: 1,116

Likes: 0

Check your rings. They might not b scratches, but domthin may be up with your rings.

Nov 25, 2012 | 11:42 AM

4x4 Bart

Fleet Mechanic

Joined: Feb 2007

Posts: 1,326

Likes: 48

From: Middle TN

Running without EGR working = high cyl temps and ring damage ???

Nov 25, 2012 | 07:39 PM

Harte3

Postmaster

Joined: Dec 2006

Posts: 3,603

Likes: 10

From: Spokane, WA

That might be caused by piston slap. Do a Google search on piston slap and cylinder scuffing.

Nov 25, 2012 | 09:16 PM

fordman75

Lead Driver

Joined: Dec 2000

Posts: 6,302

Likes: 47

From: South central, Minnesota

Quote:

Originally Posted by Harte3

That might be caused by piston slap. Do a Google search on piston slap and cylinder scuffing.

Could also be a cracked piston skirt. Which isn't to uncommon with a stock piston in a 300.

Nov 26, 2012 | 08:35 AM

Fordownsall

Senior User

Joined: Jun 2010

Posts: 192

Likes: 0

From: Tennessee

Quote:

Originally Posted by Jason6969

no scratches felt when you run your fingernail across it. carbon? only visible in a couple cylinders this is the worst one.

Thanks,
Ross

With that being said, and the way it looks I wouldn't call it metal-to-metal contact. If he had scuffed or scored pistons, rings, or cyl. walls he would have excess oil bypassing rings and getting into the comb. chamber.

It looks like light up and down scuffing, normal. If your pistons have markings you could make sure they are faced in the right direction and in correct relationship with the connecting rods.

If you are worried about it, take some measurements? Check for out-of-roundness and/or taper. If it checks out good keep on truckin

Nov 28, 2012 | 03:00 PM

4x4 Bart

Fleet Mechanic

Joined: Feb 2007

Posts: 1,326

Likes: 48

From: Middle TN

O.K. guys look at how high up in the cyl the marks are. It cant' be the piston skirt.
It's not the top of the piston either because the top of the piston extends above the marks.
It's the rings.